DAMASCUS, May 4 -- The inspectors of the Organization for the Prohibition of Chemical Weapons (OPCW) finished their work in inspecting alleged chemical attack in the Syrian capital Damascus' eastern Douma district, the OPCW said in a statement on Friday.

The statement said the initial deployment of the fact-finding mission of the OPCW to gather facts in Douma is completed, adding that the collected samples were sent to the organization's laboratories for analysis that could take "at least three to four weeks."

Meanwhile, the OPCW said it cannot determine the timeframe on when its report about its findings in Douma will be presented to the States Parties.

The arrival of the OPCW team last month to Damascus came after the Syrian government invited the OPCW to investigate the April 7 incident, in which the rebels and activists accused the Syrian forces of using chlorine gas in an attack on Douma.

At the time, the Syrian government denied the allegations and said the rebels and their foreign backers were fabricating events to attract foreign military action.

On April 14, the United States, France, and Britain launched a series of missile strikes on Syrian positions over the allegations, and the OPCW team arrived on the same day after the strikes were over.

However, the Syrian government maintained that it demands an inspection into the allegations to "expose the lies of the Western powers."